Add RequiredHostSpec

We want to gracefully handle the case where there's no booted/staged
image - i.e. when there's no spec.

However we only support deploying a container image.  So add
a `RequiredHostSpec` that is like `HostSpec` but without the
`Option`.

This drops out a few unnecessary `Option`-juggling in the deploy
code.

Prep for adding configmaps to the spec.

Signed-off-by: Colin Walters <[email protected]>

lib/src/cli.rs

@@ -19,6 +19,7 @@ use std::io::Seek;
 use std::os::unix::process::CommandExt;
 use std::process::Command;
 
+use crate::deploy::RequiredHostSpec;
 use crate::spec::Host;
 use crate::spec::ImageReference;
 
@@ -290,6 +291,7 @@ async fn upgrade(opts: UpgradeOpts) -> Result<()> {
             "Booted deployment contains local rpm-ostree modifications; cannot upgrade via bootc"
         ));
     }
+    let spec = RequiredHostSpec::from_spec(&host.spec)?;
     let booted_image = status
         .booted
         .map(|b| b.query_image(repo))
@@ -334,7 +336,7 @@ async fn upgrade(opts: UpgradeOpts) -> Result<()> {
             println!("Staged update present, not changed.");
         } else {
             let osname = booted_deployment.osname();
-            crate::deploy::stage(sysroot, &osname, &fetched, &host.spec).await?;
+            crate::deploy::stage(sysroot, &osname, &fetched, &spec).await?;
             changed = true;
             if let Some(prev) = booted_image.as_ref() {
                 let diff = ostree_container::ManifestDiff::new(&prev.manifest, &fetched.manifest);
@@ -386,6 +388,7 @@ async fn switch(opts: SwitchOpts) -> Result<()> {
     if new_spec == host.spec {
         anyhow::bail!("No changes in current host spec");
     }
+    let new_spec = RequiredHostSpec::from_spec(&new_spec)?;
 
     let fetched = pull(repo, &target, opts.quiet).await?;
 
@@ -429,17 +432,13 @@ async fn edit(opts: EditOpts) -> Result<()> {
     if new_host.spec == host.spec {
         anyhow::bail!("No changes in current host spec");
     }
-    let new_image = new_host
-        .spec
-        .image
-        .as_ref()
-        .ok_or_else(|| anyhow::anyhow!("Unable to transition to unset image"))?;
-    let fetched = pull(repo, new_image, opts.quiet).await?;
+    let new_spec = RequiredHostSpec::from_spec(&new_host.spec)?;
+    let fetched = pull(repo, &new_spec.image, opts.quiet).await?;
 
     // TODO gc old layers here
 
     let stateroot = booted_deployment.osname();
-    crate::deploy::stage(sysroot, &stateroot, &fetched, &new_host.spec).await?;
+    crate::deploy::stage(sysroot, &stateroot, &fetched, &new_spec).await?;
 
     Ok(())
 }

lib/src/deploy.rs

@@ -14,13 +14,31 @@ use ostree_ext::ostree::Deployment;
 use ostree_ext::sysroot::SysrootLock;
 
 use crate::spec::HostSpec;
+use crate::spec::ImageReference;
 
 // TODO use https://github.com/ostreedev/ostree-rs-ext/pull/493/commits/afc1837ff383681b947de30c0cefc70080a4f87a
 const BASE_IMAGE_PREFIX: &str = "ostree/container/baseimage/bootc";
 
 /// Set on an ostree commit if this is a derived commit
 const BOOTC_DERIVED_KEY: &str = "bootc.derived";
 
+/// Variant of HostSpec but required to be filled out
+pub(crate) struct RequiredHostSpec<'a> {
+    pub(crate) image: &'a ImageReference,
+}
+
+impl<'a> RequiredHostSpec<'a> {
+    /// Given a (borrowed) host specification, "unwrap" its internal
+    /// options, giving a spec that is required to have a base container image.
+    pub(crate) fn from_spec(spec: &'a HostSpec) -> Result<Self> {
+        let image = spec
+            .image
+            .as_ref()
+            .ok_or_else(|| anyhow::anyhow!("Missing image in specification"))?;
+        Ok(Self { image })
+    }
+}
+
 pub(crate) async fn cleanup(sysroot: &SysrootLock) -> Result<()> {
     let repo = sysroot.repo();
     let sysroot = sysroot.sysroot.clone();
@@ -96,21 +114,16 @@ pub(crate) async fn stage(
     sysroot: &SysrootLock,
     stateroot: &str,
     image: &LayeredImageState,
-    spec: &HostSpec,
+    spec: &RequiredHostSpec<'_>,
 ) -> Result<()> {
     let merge_deployment = sysroot.merge_deployment(Some(stateroot));
     let origin = glib::KeyFile::new();
-    let ostree_imgref = spec
-        .image
-        .as_ref()
-        .map(|imgref| OstreeImageReference::from(imgref.clone()));
-    if let Some(imgref) = ostree_imgref.as_ref() {
-        origin.set_string(
-            "origin",
-            ostree_container::deploy::ORIGIN_CONTAINER,
-            imgref.to_string().as_str(),
-        );
-    }
+    let imgref = OstreeImageReference::from(spec.image.clone());
+    origin.set_string(
+        "origin",
+        ostree_container::deploy::ORIGIN_CONTAINER,
+        imgref.to_string().as_str(),
+    );
     crate::deploy::deploy(
         sysroot,
         merge_deployment.as_ref(),
@@ -120,17 +133,15 @@ pub(crate) async fn stage(
     )
     .await?;
     crate::deploy::cleanup(sysroot).await?;
-    if let Some(imgref) = ostree_imgref.as_ref() {
-        println!("Queued for next boot: {imgref}");
-        if let Some(version) = image
-            .configuration
-            .as_ref()
-            .and_then(ostree_container::version_for_config)
-        {
-            println!("  Version: {version}");
-        }
-        println!("  Digest: {}", image.manifest_digest);
+    println!("Queued for next boot: {imgref}");
+    if let Some(version) = image
+        .configuration
+        .as_ref()
+        .and_then(ostree_container::version_for_config)
+    {
+        println!("  Version: {version}");
     }
+    println!("  Digest: {}", image.manifest_digest);
     ostree_container::deploy::remove_undeployed_images(sysroot).context("Pruning images")?;
 
     Ok(())